THERAPY OF HUMAN OVARIAN-CARCINOMA XENOGRAFTS USING DOXORUBICIN ENCAPSULATED IN STERICALLY STABILIZED LIPOSOMES

Background. This study compared the therapeutic effects of doxorubicin hydrochloride in saline and in sterically stabilized, long-circulatin g liposomes composed of hydrogenated soy phosphatidylcholine/cholester ol/polyethylene glycol-distearoyl-phosphatidyl-ethanolamine (Doxil). M ethods. The drug formulations were injected intravenously or intraperi toneally to treat the human ovarian carcinoma HEY, which was implanted subcutaneously or intraperitoneally into mature female Swiss nude mic e. Results. The long-circulating liposome formulation was significantl y more effective than was the free drug in inhibiting tumor growth and in producing cure. The liposome formulation was significantly less to xic than was the free drug. This is the first demonstration of the the rapeutic effectiveness of doxorubicin in sterically stabilized liposom es against human tumor xenografts. Conclusions. The encapsulation of d oxorubicin in long-circulating liposomes significantly enhanced the th erapeutic efficacy of the drug against a human ovarian carcinoma.